I have date fields in the pdf form in which the signed date is inserted when each user signs the form. Although the Digital Signature property in pdf provides date property on the signature image. But we have a business requirement to show date field separately on pdf form. Suppose User1 signs the application and the date is inserted in its corresponding date field. But when User2 signs the application and the date is inserted the signatures of User1 gets invalidated.
Is there any way by which pdf field can be made editable even after one user signs the application?
PDF supports multiple signatures on a single form or document. When using a form, you can use field collections to associate specific fields to a certain signature and lock those fields after signing, while leaving other fields accessible. There are many posts throughout this forum that discusss this functionality, here is one... http://forums.adobe.com/thread/769340
As for signature status, applying a second signature (or more) after a form or document has been signed will NOT invalidate the original signature, however it will change the status of the original signature to something like "Valid with signed changes". Each subsequent signature will change the status of the previous signature, but this is not the same as invalidating a signature.
This behaviour is by design as a signature applied to a PDF signs the entire byte range of the PDF, not just a portion of it.
Thanks for your quick response.
The signature doesn't get invalidate untill an unless any field in the pdf is modified. After signing the pdf i want to insert date in the pdf . i.e. it will modify the pdf. After the pdf is modified (date is inserted in the signed pdf), the signature gets invalidated (the red cross apprears on the signature field).